Anonymous, “Considerations on the language of communication between the Chinese and European governments”, in “The Chinese Repository”, vol XIII, June 1844, no. 6, pp. 281–300.
Available on Google Books: http://books.google.com.au/books?id=6wEMAAAAYAAJ
Modern reprint exists, ISBN 1-4021-5630-8

The American Diplomat was probably Caleb Cushing, who negotiated the treaty of Wang Hiya. He was said to have advocated the use of Manchu as the primary language of diplomatic communication with China.

As for Bucin’s questions: the suffix -tala/-tele is not fully productive in Manchu, and I think it is normally a verbal suffix anyway. It would be better to say “1844 aniya de isitala”.

If you want to say, “The official language of China was Manchu, so emissaries from other countries learned the Manchu language,” you might say “Dulimbai gurun i gisun manju gisun bime, gūwa gurun ci jihe elcin manju gisun be taciha”. (The Manchus didn’t call China “Manju gurun”, because they had a delicate ethnic balance to maintain with the more numerous Han.)

i think “aniyatala” and “ohobe dahame” are not a pure manchu idioma, how can i write it correctly?